A snack food popular in the southern United States. A moon pie consists of a marshmellow sandwiched between two cookie-shaped graham crackers, which is then dipped in chocolate. Moon pies are sometimes sold as "marshmellow pies" or "scooter pies" in other areas of the country. In Canada, a moon pie is called a "wagon wheel."

In the 1950s, a moon pie and an R.C. Cola was known as a "working man's lunch."

Possibly the most disgusting sex-act ever known to both man and machine.
The act of going to a party of drunkeness, getting someone to pass out from drunkeness (amongst other things), pulling down ones (meaning yours) pants, taking a massive poo on their chest, ejaculating gooey substance on the poo, and lastly, taking another massive poo on the gooey substance of which is atop the mountainous poo-mountain below it.
As soon as this act of nastyness is complete, one (meaning you) would be best to completely dissapear from the party.

Chris (by the urbandictionary.com rules, he's not a real person-don't try to find him, it'd be a waste of time) totally decided to moon pie that chick.
It was so nasty, I couldn't stop vomitting.

When nearing climax during intercourse, lift the breast of your partner and proceed to ejaculate underneath her breast. Then mash it back down on her chest so that it resembles a moonpie aka marshmallow pie.

"I gave Reagan a moonpie a few weeks back and now she won't even speak to me"

The female version of a fruit basket or a sluttier version of mooning; when a women bends over and you can see her vagina and asshole.

Hey fellow drunken ladies let us moon pie that truck driver.
Kaitlyn always goes commando so I make sure to drop my pencil when she wears a short skirt, here's hoping for moon pie.
There's nothing better than a moon pie in the morning.